I have to add i finally got my hands on 2 mongoose,s orange and blue
now just waiting on my favourite
Not to burst any bubbles here, but did you know that there is a third mongoose? It comes with a Crimson and Silver CQB Spartan.
Main link:
http://www.spawn.com/toys/product.aspx?product=4028
Likewise when you say waiting on your favorite, did you know that the picture you posted was NOT of Master Chief? In fact the one you posted is a Spartan from the "Halo Wars" video game, not Halo, Halo 2 or Halo 3. There is a significant difference in the armor and coloration.
For the record I too am awaiting this specific figure. It was to be in the latest wave of figures that is currently out in stores, but for some reason McFarlane pulled it back. It will now be coming out in a two-pack with the actual Master Chief. See pic below:

Here's the main link:
http://www.spawn.com/toys/product.aspx?product=4100I've been collecting this line since McFarlane took it over. I've enjoyed it quite a bit and it's not really expensive to collect, save a few exclusives, mostly stemming from overseas. Still, it's nothing compared to the money I've spent in the past on SW.
Jesse, if you're interested in just the accessories, then you might be interested in the weapons pack. They issued one a wave or so ago and are reissuing it. Here it is:

And the main link:
http://www.spawn.com/toys/product.aspx?product=4093It's a decent mix of both Human and Covenant weaponry. Though if you're after an AR or BR, then yeah, you're going to have to buy the figures for now. I'm hoping for a NEW Weapons pack that includes those weapons among others, instead of this reissue. But you take what you can get I suppose.